Daniel Stack will never forget being medevaced out of Southeast Asia during the Vietnam War, surrounded by servicemen with far more devastating injuries than his skin condition.

“I saw firsthand the suffering of those guys who were really wounded,” said Mr. Stack, 67, an Uxbridge resident who served in the U.S. Air Force.

He committed himself then to helping his fellow disabled veterans. Now he serves as Massachusetts department adjutant and CEO of Disabled American Veterans, a nonprofit organization that assists and advocates for veterans.